1. Field of the Invention
This invention relates to an arrangement for the optoelectrical scanning of a master, where a scanning device which has a plurality of scanning elements simultaneously scans a plurality of parallel lines of a row, and where the master is moved at right angles to the direction of scanning.
2. DESCRIPTION OF THE PRIOR ART
With known facsimile machines, which are also known as remote copiers, a master to be scanned is clamped on a revolving roll and the master is scanned line-by-line with a scanning element, for example a photoconductive cell or a phototransistor. Scanning signals produced by this scanning elements are transmitted to a receiving unit where, line-by-line, point-by-point, the scanned master is reproduced. With mechanical printing systems, approximately six minutes are required to reproduce a din A4 page and with electrographic processes about two to three minutes are required.
The German published application No. 25 18 370 discloses a scanning device in which a plurality of lines are scanned simultaneously in order to reduce the time needed for scanning the master. The master to be scanned is moved in steps at right angles to the direction of scanning in a flat-bed scanner. The scanning device has a plurality of scanning elements, photodiodes for example, and the scanning device is moved backwards and forwards over the master. While the scanning device reverses its direction of movement after completing scanning in one direction, the master is displaced by one forward feed step at right angles to the direction of scanning. Due to the plurality of scanning elements, the master is scanned simultaneously along a multiplicity of parallel lines. The number of lines is the same as the number of scanning elements.
In a publication of B. Peukert and H. Senger: Schreibstation PT80, Siemens Journal 51 (1977), Vol. 4, p 215-218, a printing station is described which can be employed instead of remote or data printing machines. The printing station has a mosaic printing head which presents the characters to be printed in a grid of 12.times.9 matrix points. The mosaic printing head can also take the form of a needle printing head, containing 12 printing needles driven by means of plunger moving coils which are staggered in two rows for two groups of six needles.
The mosaic printing head, however, can also take the form of an ink printing head having 12 jets controlled by piezoceramic means.
If, when using a printing station of this kind, graphic specimens are also to be reproduced, in addition to alpha-numeric characters and special characters, and the printing station is therefore also to be used as a facsimile receiver at the same time, then it is advantageous to have a scanning device with which a master to be transmitted can be scanned.